These were all written a while back. The original one was done when their was only 1 android phone. There are lots of alternatives to SIPdroid now, and loads of handsets to run the apps on. Though they are slightly dated, these guides cover the basics of setting up a working configuration.

With that being said. Please understand I am not capable of testing on every device or every carrier. If you have followed the guides, and still need help, visit the forum for your device @ XDA. They have a wealth of information on everything Android related, and are quite helpful. You will get your question answered a lot sooner over there.